Etudes des equilibres solide-liquide du systeme binaire AgPO3-LaP3O9

The AgPO₃-LaP₃O₉ system was investigated for the first time by DTA, X-ray diffraction, and IR spectroscopy. The only definite compound observed in the system was AgLa (PO₃)₄, which melted incongruently at 800°C. The method of preparation, powder diagram and crystallographic data of AgLa(PO₃)₄ are given. AgLa(PO₃)₄ crystallises in the monoclinic system P_21/C with a unit cell: a = 12.38(2) Å; b = 12.88(2) Å; c = 7.33(1) Å; β = 127°91(6) z = 4. Its IR absorption spectrum is typical of a chain phosphate.     

In Vitro Alpha-Amylase and Alpha-Glucosidase Inhibitory Activity and In Vivo Antidiabetic Activity of Withania frutescens L. Foliar Extract

Withania frutescens L. is a wild perennial woody plant used by the local population for diverse therapeutic purposes. This work aims to study for the first time the potential inhibitory effect of this plant hydroethanolic extract on α-amylase and α-glucosidase activities using in vitro methods and its antidiabetic and antihyperglycemic activities using alloxan-induced diabetic mice as a model for experimental diabetes. Two doses were selected for the in vivo study (200 and 400 mg/kg) and glibenclamide, a well-known antidiabetic drug (positive control) in a subacute study (28 days) where the antihyperglycemic activity was also assessed over a period of 12 h on diabetic mice. The continuous treatment of diabetic mice with the extract of Withania frutescens for 4 weeks succeeded to slowly manage their high fasting blood glucose levels (after two weeks), while the antihyperglycemic test result revealed that the extract of this plant did not control hyperglycemia in the short term. No toxicity signs or death were noted for the groups treated with the plant extract, and it shows a protective effect on the liver and kidney. The in vitro assays demonstrated that the inhibition of alpha-amylase and alpha-glucosidase might be one of the mechanisms of action exhibited by the extract of this plant to control and prevent postprandial hyperglycemia. This work indicates that W. frutescens have an important long term antidiabetic effect that can be well established to treat diabetes.     

Synthesis and characterization of 5,10,15,20-tetra[3-(3-trifluoromethyl)phenoxy] porphyrin

The newly synthesized 5,10,15,20-tetra[3-(3-trifluoromethyl)phenoxy]porphyrin, TTFMPP, has been characterized using mass spectroscopy, 1H-, 13C- and 19F-NMR, MALDI-TOF mass spectrometry, UV-Vis and fluorescence spectrophotometry, and cyclic voltammetry. The NMR confirmed the structure of the compound and the mass spectrum was in agreement with the proposed molecular formula. The UV-Vis absorption spectrum of TTFMPP shows characteristic spectral patterns similar to those of tetraphenyl porphryin, with a Soret band at 419 nm and four Q bands at 515, 550, 590, and 648 nm. Protonation of the porphyrin with TFA resulted in the expected red shift of the Soret band. Excitation at 419 nm gave an emission at 650 nm. The quantum yield of the porphyrin was determined to be 0.08. Cyclic voltammetry was used to determine the oxidation and reduction potentials of the new porphyrin. Two quasi-reversible one-electron reductions at -1.00 and -1.32 V and a quasi-reversible oxidation at 1.20 V versus the silver/silver chloride reference electrode with tetrabutylammonium tetrafluoroborate as the supporting electrolyte in methylene chloride were observed.     

Influence of Trans Fat on Skin Damage in First‐Generation Rats Exposed to UV Radiation

The influence of trans fatty acids (TFA) on lipid profile, oxidative damage and mitochondrial function in the skin of rats exposed to ultraviolet radiation (UVR) was assessed. The first‐generation offspring of female Wistar rats supplemented from pregnancy with either soybean oil (C‐SO, rich in n–6 FA; control group) or hydrogenated vegetable fat (HVF, rich in TFA) were continued with the same supplements until adulthood, when half of each group was exposed to UVR for 12 weeks. The HVF group showed higher TFA cutaneous incorporation, increased protein carbonyl (PC) levels, decreased functionality of mitochondrial enzymes and antioxidant defenses of the skin. After UVR, the HVF group showed increased skin thickness and reactive species (RS) generation, with decreased skin antioxidant defenses. RS generation was positively correlated with skin thickness, wrinkles and PC levels. Once incorporated to skin, TFA make it more susceptible to developing UVR‐induced disorders.     

Highly Resolved LES and URANS of Turbulent Buoyancy-Driven Flow Within Inclined Differentially-Heated Enclosures

In the present study, both LES and unsteady RANS computations are presented, for turbulent natural convection of air inside differentially-heated rectangular tilted cavities using a finite volume code (Code_Saturne), for an aspect ratio of H/L?=?28.6 and Rayleigh number of 0.86×10⁶. Attention is focused on two angles of inclination: 15° to the horizontal with hot lower and cold upper wall, the 15° unstable case, and the mirror image of this case where the angle is the same but with a hot upper and cold lower wall, the 15° stable case. In accordance with recent experimental data, the LES computations for both the stable and unstable tilted cavities returned three-dimensional time-averaged flow fields. In the case of the unstably stratified enclosure, the flow is highly unsteady with coherent turbulent structures in the core of the enclosure. Time-averaged temperature, velocity and resolved turbulence intensities resulting from LES computations show close agreement to measured data. Subsequent comparisons of different URANS schemes with LES are used in order to explore to what extent these models are able to reproduce the large-scale unsteady flow structures. All URANS schemes have been found to be able to reproduce the 3-D unsteady flow features present in the 15° unstable cavity. However, the low-Reynolds-number model tested, as well as requiring a high resolution near-wall grid, also needed a finer grid in the core region than the high-Reynolds-number models, thus making it computationally very expensive. Flow within the 15° stable cavity also shows some 3-D features, although it is significantly less unsteady, and the URANS models tested here have been less successful in reproducing this flow pattern. The overall heat transfer is presented here for both differentially heated enclosures.     

Anticancer Potential of Diiron Vinyliminium Complexes

Invited for the cover of this issue is the group of Fabio Marchetti at the Università di Pisa and Paul J. Dyson at Ecole Polytechnique Fédérale de Lausanne (EPFL). Read the full text of the article at 10.1002/chem.201902885 .     

Anacyclus pyrethrum (L): Chemical Composition,Analgesic, Anti-Inflammatory,and Wound Healing Properties

Background: Anacyclus pyrethrum (A. pyrethrum) is a wild species belonging to the family Asteraceae, which is used in traditional medicines. Aim of the study: This work was undertaken to study the chemical composition, analgesic, anti-inflammatory, and wound healing properties of hydroalcoholic extracts of different parts (roots, seeds, leaves, and capitula) of A. pyrethrum. Material and Methods: The phytochemical analysis of the studied extracts was conducted by GC-MS. The analgesic activity was evaluated in mice using acetic acid and formaldehyde methods. The anti-inflammatory activity was tested using the inhibitory method of edema induced in rats. The healing activity of the hydroethanolic extracts was explored by excision and incision wound healing models in rats. Results: The phytochemical analysis of the studied plant extracts affirmed the presence of interesting compounds, including some newly detected elements, such as sarcosine, N-(trifluoroacetyl)-butyl ester, levulinic acid, malonic acid, palmitic acid, morphinan-6-One, 4,5.alpha.-epoxy-3-hydroxy-17-methyl, 2,4-undecadiene-8,10-diyne-N-tyramide, and isovaleric acid. The extracts of different parts (roots, seeds, leaves, and capitula) exhibited promising anti-inflammatory, analgesic, and wound healing effects, with percentages of inhibition up to 98%, 94%, and 100%, respectively. Conclusion: This study might contribute towards the well-being of society as it provides evidence on the potential analgesic, anti-inflammatory, and wound healing properties of A. pyrethrum.     

Antiproliferative and bactericidal activity of diiron and monoiron cyclopentadienyl carbonyl complexes comprising a vinyl-aminoalkylidene unit

A series of diiron complexes with two cyclopentadienyls, two carbonyls, and one bridging vinyl-aminoalkylidene as ligands, [ 3a – h ]CF₃SO₃ and [ 4a – d ]CF₃SO₃, was synthesized in 66–94% yields from diiron μ-aminocarbyne precursors. The subsequent reactions with pyrrolidine led to selective fragmentation to aminoalkylidene-ferracyclopentenone derivatives ( 5a – h and 6a – c ) in 30–84% yields. The compounds were characterized by elemental analysis, Fourier transform infrared and NMR spectroscopy, and by single crystal X-ray diffraction in three cases. The stability in aqueous media relevant to biological trials, the carbon monoxide release, and the catalytic activity in NADH oxidation were evaluated for selected compounds by NMR spectroscopy and gas chromatography. The in vitro antiproliferative activity of the compounds was determined towards cancer (A2780, A2780cisR) and noncancer (HEK-293) cell lines. Moreover, the antibacterial activity was tested on Gram-positive (vancomycin-resistant E. faecium and methicillin-resistant S. aureus) and Gram-negative strains (A. baumannii and P. aeruginosa).